1. Field of the Invention
This invention relates generally to a solid state color camera employing solid state image senors and more particularly to a camera the requires two or three image sensors with horizontally extending stripe color filters.
2. Description of the prior art
When a solid state image sensor, such as a CCD, is used as a television camera, input light information from an object image is sampled at every picture element and then converted into a video signal. If the alignment pitch of picture elements in the horizontal direction of the CCD is taken as .tau..sub.H, the sampling frequency, f.sub.c, maybe expressed as .sup.1 .tau..sub.H. If the input light information of each picture element is read sequentially in the horizontal direction, DC components, S.sub.DC, as an output video signal of, one horizontal line period, and side band components, S.sub.SB, which are obtained by modulating the sampling frequency f.sub.c with the DC components S.sub.DC, are obtained. The side band components, S.sub.SB, become upper and lower side bands with the sampling frequency, f.sub.c, being at the center. If the band of DC components S.sub.DC is selected sufficiently wide to obtain the desired resolution, the side band components S.sub.SB become superimposed on the DC components, S.sub.DC. As a result, there appears a sampling error which is caused by Nyquists sampling theorem. If an image is reproduced from the above state of a video signal, a flicker may appear in the reproduced picture.
Since this flicker is caused by the sampling error, if the band of the DC components S.sub.DC is limited within a band narrower than one half, the sampling frequency, f.sub.c, the sampling error and hence the flicker in the reproduced picture can be avoided. However, if the band of the DC components, S.sub.DC, is limited as described above, the resolution is deteriorated. If the band of the DC components, S.sub.DC, is selected so as not to deteriorate the resolution and the sampling error is prevented, it would be enough to select the sampling frequency f.sub.c at a suitably high number. Since the sampling frequency f.sub.c is a product of the number, n, of picture elements in the horizontal direction and the horizontal scanning frequency f.sub.H (f.sub.c = n.sup.. f.sub.H), to make the sampling frequency f.sub.c high enough to the sampling error, it is necessary to increase the number of the picture elements to the point where the manufacture of the CCD becomes difficult and costly.